<!doctype HTML>
<html>
<head>
<style>
html {
  background: lightpink;
}
div {
  position: relative;
  width: 200px;
  height: 200px;
}

.outer {
  background-color: blue;
  box-shadow: -50px -50px 0px 0px rgba(0,0,0,1);
  left: 100px;
  top: 100px;
}

.inner {
  background-color: red;
  left: 50px;
  top: 50px;
}

</style>
</head>
<body>
</body>
<div class="outer">
  <div class="inner"></div>
</div>
</html>
